1. Field of the Invention
In preferred embodiments, the present invention relates to methods for polymerizing a monomer solution within a cavity such that the outer surface of the cavity has a smooth surface. More specifically, methods are disclosed for making a sensor comprising functional chemistry immobilized within a polymeric matrix disposed within a cavity along the sensor, wherein the sensor has a smooth outer surface.
2. Description of the Related Art
Polymers are widely used for coating surfaces in a wide variety of applications. For example, polymers are used to coat metals, fabrics, paper and glass to provide corrosion resistance, water resistance and insulation. With respect to biomedical applications, polymers can be used to increase the biocompatibility of a surface or to provide other desirable properties, such as immobilizing functional chemistries for intravascular deployment.
A variety of surface coating methods exist. One method involves dipping the surface to be treated in a solution or emulsion of a polymer and then either letting it dry or transferring the surface into a coagulation bath which is capable of extracting the solvent from the polymer solution. If the coat needs to be made thicker, the process can be repeated to add another layer of polymer to the coated surface.
In another method, the polymer is formed into a powder that is electrostatically sprayed onto a neutrally or oppositely charged surface. The charged polymer powder particles electrostatically adhere onto the surface. Heat treatment of the powdered surface cures and finishes the coated surface.
In another method, the surface is heated and immersed in a fluidized bed of powdered polymer particles. The fluidized bed of polymer particles is formed by aerating a bed of polymer particles with a gas. The powder adheres to the heated surface, which is then removed from the fluidized bed and further heated to cure and finish the coated surface.
There remains an unmet need for methods of making an analyte sensor, by immobilizing function chemistries in a polymeric matrix within a cavity in the sensor, such that the chemistries retain their functionality and wherein the outer surface of the sensor is smooth and non-thrombogenic.